Method and apparatus for counting impulses



Oct. 10, 1961 C. F. STRANDBERG METHOD AND APPARATUS FOR COUNTINGIMPULSES 3 Sheets-Sheet 1 Filed Nov. 8. 1957 [bar/e5 Jim/20%;

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5 Sheets-Sheet 2 C. F. STRANDBERG METHOD AND APPARATUS FOR COUNTINGIMPULSES Filed Nov. 8. 1957 Oct. 10, 1961 Patented Oct. 10, 19.51

3,003,691 METHOD AND APPARATUS FUR COUNTING ULSES This inventioncomprises a method and an apparatus for counting impulses from aplurality of random sources without error and includes a circuitprovision which permits two or more such counters to be connected to onemachine-located, impulse switch.

In my prior application Serial No. 572,902 now Patent No. 2,831,635 ofwhich this application is a continuation in part filed March 21, 1956,entiled Random Information Counting Method and Apparatus, I havedescribed apparatus which receives impulses at random and arranges themsequentially for counting purposes. The apparatus therein describedcomprises a plurality of impulse switches and a rotary sampling switchincluding a plurality of contacts in circuit with the respective impulseswitches. The rotor of the sampling switch sweeps each contactsequentially and applies the impulse stored thereon to the grid of animpulse receiving tube. The tube on receiving an impulse at its gridfires and activates a counter actuating circuit. Important elements ofthis apparatus are memory capacitors in circuit with each impulse switchand its respective contact on the rotary sampling switch. impulsesgenerated at random by the plurality of impulse switches are stored inthe memory capacitors until such time that they are received by thesampling rotor.

With references to application Serial No. 572,902 now Patent No.2,831,635 of which this application is a continuation in part, it hasbeen found that positive error of the order of one part in ten thousandis possible when an impulse is received at the instant the rotor arm isdeparting from the particular contact being energized. The old methodemploys two means for limiting this error: (a) use of short-durationpulse making switches, and (b) a resistance-capacitance network intendedto delay the appearance of the signal to the impulse receiving tube forcounting until erase or discharge has been accomplished.

The new method provides for positive erase by feeding back to eachcontact and its associated capacitor a voltage which is negative withrespect to that appearing across the memory capacitor. In order not toerase charges which have not been counted, the feedback device is madeto operate only when a count has been registered.

Another object of this invention is to provide a unidirectional electronvalve in the memory capacitor charg ing path to ground in order topermit two or more counters to receive impulses from the same impulseswitch without interaction between the two counters.

The method disclosed in application Serial No. 572,902, now Patent No.2,831,635, does not allow the use of two or more counters connected tothe same impulse switch, which imposes practical limitations upon asystem of counters.

An example of the need for multiple connection of counters is in atextile weave room, where the object is to count picks from groups offorty or fifty looms for worker pay determination and simultaneously tocount picks from certain looms in several groups for determination ofproduction by style of cloth being woven. The lines from the loomsterminate in a panel board, from which selected machines are connectedto counters by means of patch cords similar to those used by telephoneoperators.

Other advantages in being able to connect two or more counters to onemachine-located, impulse switch include registration of inventorysimultaneous with pr0- duction counting and measurements of machinespeed and eficiency without interference with counting.

Another object of this improved apparatus is to further the degree ofintegration of the impulse applied to the impulse receiving tube byinserting an induction coil in the input impedance network.

Other advantages and features of the invention will become apparent fromthe following description taken in conjunction with the accompanyingdrawing, wherein like characters of reference are used to designate likeparts, and wherein:

FIGURE 1 is a diagrammatic illustration of the counting apparatus inaccordance with the invention;

FIGURE 2 is a diagrammatic illustration of a modification of thecounting apparatus in accordance with the invention; and

FIGURE 3 is a simplified circuit diagram showing only those componentsaffected in two counters connected to one impulse switch.

FIGURE 4 is a schematic detail view of a modification of the rotarysample switch used in accordance with the invention.

FIGURE 5 is a partial circuit drawing showing a modified form of mycounting apparatus used for counting machine-hours of production from agroup of machines.

In accordance with the invention each information source is providedwith an electric impulse switch designated generally by referencenumeral 10. One contact 23 of each impulse switch is connected to acommon ground 25. A second contact 22 is connected by conductor 24 to aremote control panel 26 at which there is provided a rotary samplingswitch 27. The latter comprises a plate 28 having a plurality ofcircumferentially spaced contacts or segments 29 theron, the number ofthese contacts or segments corresponding to the number of informationsources to be counted. The plate 28 also carries a rotor arm 39 which issuitably driven at a fixed rate so as to successively engage thecontacts 29 each once during a certain period.

The wires or conductors 24 from the several switches 10 are connected tothe respective contacts 29 of the sampling switch 27, it being noted forsimplicity of illustration in the accompanying FIGURE 1, only several ofsuch connections have been shown.

The sampling switch 2"] is adapted to retain an electrical impulse onany one of the contacts 29 until such impulse is picked up by the rotorarm 34) and transmitted by means hereinafter described to a suitablecounter 31. Moreover, after the impulse is picked up by the rotor arm,the segment or contact 29 must be free of the impulse. Finally, therotor arm 30 must make contact with all the segments in less time thancan possibly exist between two successive impulses applied to anyparticular segment.

In order to satisfy the above conditions, a plurality of memorycapacitors 32 are provided in circuit with the respective conductors 24leading to the respective segments 29 and a common direct currentsource. The direct current source may comprise any conventional powersupply but has been shown by way of illustration to consist of arectifier network comprising a transformer 40, a rectifier element 41,and a filtering capacitor 42. Alternating current is supplied to theprimary of transformer 40 from a suitable source 35 by way of a pair ofconductors connected to terminals 1 and 2 of terminal board 86, contacts2 and 6 of plug connector 87, and corresponding contacts 2 and 6 of jack88 mounted on control panel 26. Conductors 89 and 90 connect theswitches are momentarily closed thereby making the 7 segments 29positive with respect to the cathode 44 of a suitable impulse receivingtube 34. The charge path for each of the memory capacitors 32 includesthe direct current power supply (comprising transformer 40, rectiher 41and capacitor 42) cathode grounded diode 72 and the impulse switch 16associated with a particular memory capacitor.

The impulse receiving tube 34 may be a gas filled tetrode asillustrated, comprising in addition to the cathode 44 a control grid 45,a plate 46, a screen grid 47, and a filament 48. The filament issupplied with alternating current by transformer 49. The plate issupplied with potential from across transformer 43. A bias voltage isapplied to the grid 45 of tube 34 through resistor 70 from a negativevoltage source 52 subsequently to be described.

The rotor arm 30 is rotated at a constant speed by a suitable drivemechanism 43. The speed at which the rotor is driven is selected to begreater than the rate of occurrence of the impulses so that the rotorarm 30 contacts all the, segments 29 in less time than exists betweentwo successive impulses applied to any givensegment.

When the rotor arm 30 picks up an impulse from any one of the segments29, the grid 45 of the tube 34 is rendered positive, causing the tube toconduct. The counter 31 is in circuit with a source of alternatingcurrent 35 and with the tube 34 through a relay 36, the closing of thelatter being arranged to actuate the counter each time positivepotential is delivered to the grid of the tube 34. A damping capacitor38 is placed across the relay coil 39 to improve the relay response.

Although the response of the relay 36 is improved by the capacitor 33for the reason that the voltage applied to it is a pulsating D.C.voltage, the capacitor 38 acts to lengthen the relay closure time, whichis not desirable. A second set of contacts is provided on relay 36 forthe purpose of permitting capacitor 38 to discharge rapidly through acurrent limiting resistor 92 at the instant the relay is energized thussatisfactorily reducing the closure time of relay 36.

The apparatus heretofore described except for diode 72 in the chargepath of capacitor 32 is essentially common to apparatus described in myprior application Serial No. 572,902, now Patent No. 2,831,635 and tothe random counting apparatus of the present invention. The improvementsprovided by this invention will now be described in detail.

Positive erase of any voltage which may remain on any one of thecontacts29 of the sampling switch 27 is efiected by applying to eachcontact and its associated capacitor 32 a voltage which is negative withrespect to the voltage appearing across the capacitor.

With reference to FIGURE 1, the sampling switch 27 contains two sets ofconnected contacts or segments 29, 48 and two rotors 30, 49, driventogether. FIGURE 1 shows the outer set of primary contacts 29 sampled bythe counter rotor 30 and the inner set of secondary con tacts sampled bythe erase rotor 49.

The erase rotor arm 49 is made shorter than counter rotor arm 30 and thecontact points 50, 51 on rotor arms 30 and 49 respectively are in radialalignment with the center of rotation of the rotor arms. Each secondarycontact 48 is positioned inwardly of the associated contact 29 relativeto the center of plate 28 and forwardly of contact 29 relative to thedirection of rotation of the rotor arms. This particular arrangement ofthe contacts is provided in order that the contacts 48 exposed to rotor49 are sampled later than those exposed to the counter rotor 30.

However, the invention which is to accomplish the erase function is notlimited by the particular physical arrangement of the contact segments.For instance, as illustrated in FIGURE 4, the inner set of contacts 48can be avoided completely if the two rotors blades are the same lengthand the erase rotor blade 49 is made to follow directly behind the pathof the counter rotor blade 30.

The negative erase voltage may be taken across any suitable D.C. source52 but is shown in FIGURE 1 to be taken across an alternating currentrectifier network comprising an A.C. current source 35 transformer 53,rectifier 54, smoothing capacitor 55 and output resistor 56. Capacitor55 is selected of such value that it is capable of sustaining a constantD.C. erase voltage across it, substantially not influenced by changingload conditions. From the direct current source the erase voltage isconducted by way of impedance network 57, the contacts 59 of erase relay58 and erase rotor arm 49. The coil 60 of relay 58 is in the platecircuit of impulse receiving tube 34. The erase relay 58 thereforeoperates only when tube 34 conducts and a count is received by counter31. Two sets of contacts are shown on relay 53 merely to indicate theusage of two identical relay types, 36 and 58. One set of contacts wouldperform satisfactorily for the purpose of this invention.

Assume that a count is received and registered, automatically makingoperative the erase device by applying a voltage to the erase rotorwhich is negative with respect to that which caused the counter tooperate. The erase rotor comes in contact with the segment or contactfrom which the count has been received and applies a negative pulse,thus rapidly discharging the associated capacitor 32.

Unless a count is received in time to be counted it will not be erased,since the erase device depends upon registration of a count to operate.

The means for erasing as has been described and is shown in FIGURE 1makes use of an additional set of relay contacts 59 operated by a relaycoil 60 in the plate circuit of the tube 34. Since the tube conductsonly at receipt of a count, the relay contacts 59 close at this time andapply the negative potential to the contact 48 and capacitor 32.

' Another suitable means for accomplishing erase switching is shown inFIGURE 2. A second switching tube 61, in this case a gas controlledtetrode, is connected so as to deliver a negative voltage to thecapacitor 32 at the time of registration, thus eliminating the need forrelay contacts and permitting operation at higher speed.

Tube 61 comprises a control grid 62 connected to control grid 45 of tube34, a cathode 63, plate 64, and cathode connected screen grid 65. Sincethe control grids 62 and 45 are connected and suitable cathode bias fortube 61 is obtained by a tap 66 off the output resistor 56 of rectifiernetwork 52, tube 61 will not fire until such time that a count firestube 34. When tube 61 fires a negative voltage from the plate 64 isapplied through conductors including impedance network 67 to the eraserotor 49. Plate current source for tube 61 is the residual positivevoltage across memory capacitor 32 in series with a fixed voltage of thesame polarity existing across the portion of resistor 56 shown to theright of the tap 66.

Both circuits are damped so as to time the application of the negativevoltage 50 that it is present only long enough for the erase rotor 49 toreach the contact 48. Damping capacitors 68 and 69 respectively areshown across the relay coil 60 in FIGURE 1 and across the inputresistance 70 in FIGURE 2.

As shown in FIGURES 1 and 2, the improved apparatus substitutes a coil71 for the resistor in the tube input resistance-capacitance networkillustrated in FIGURE 1 of my application S.N. 572, 902 now Patent No.2,831,635 of which this application is a continuation in part to furtherthe degree of integration.

With reference to FIGURES l and 2, a uni-directional valve, in thisinstance a vacuum diode 72 has been inserted in the memory capacitorcharging path to ground in order to permit two counters to receiveimpulses from the same impulse switch without interaction between thetwo counters. In some installations it may be desirable to connect oneor more of my counting apparatus (hereinafter called a counting unit inorder to indicate a complete counting apparatus) to the same machinelocated impulse generating switches 10. When so connected the switcheswill be component parts of plural counting units. Interaction betweenthe plural counting units would prevent their proper operation of somemeans were not provided to counteract the interaction. These meansprovided are the uni-directional valves 72 shown .in FIGURES 1 and 2.The use of these valves in the charge paths of memory capacitors 32 isnot required when only one counting unit is connected to the impulseswitches 10. They are required to prevent interaction when plural unitsare connected to the same impulse switches.

FIGURE 3 is a simplified circuit diagram showing only those componentsaffected in two counters connected to one impulse switch 10.

The addition of the vacuum tube diode, 72, prevents the memory capacitor32 contained in one counter from being discharged by the discharging ofmemory capacitor 32 contained in the other counter. In order for currentto flow in the loop from one memory capacitor contained in one counterto one memory capacitor contained in the other'counter, it must passthrough both diodes 72, 72, which is made impossible regardless ofdirection of flow, since onediode blocks current flow one way while theother diode blocks it the other. The diodes are, however arranged in thecircuit so as to permit charging of the memory capacitors 32 at the timeof momentary closure of the machine-located, impulse switch 10. Abattery 91 has been shown in FIGURE 3 as representative of a directcurrent source which may be the rectified alternating current powersupply shown in FIGURES 1 and 2. The charge path for the capacitors 32with the exception of the substitution of the battery power supply 91 isthe same as that described for FIG- URE 1. The only possible dischargepath available for the memory capacitors is through the rotary switch27.

Although the apparatus of this invention has been described relating itto its use for counting information produced at random, it may bemodified for use to count production time or machine hours ofproduction. FIG- URE 5 illustrates apparatus with which machine hours ofproduction can be counted by substituting for switch 10 switches 74which are closed while production machines 73 are operating and whichare open when the machines are idle. Only such parts of the circuits ofmy counting apparatus which are necessary to show the connection of theswitches 74 are shown in FIGURE 5. Otherwise the counting circuits maybe the same as shown in FIGURE 1 of my prior application Serial No.572,902'now Patent No. 2,831,635 of which this application is acontinuation-in-part, or in FIGURES l and 2 of this application. -Theswitches 74 may be of any type which function as described above, butfor purposes of illustration a centrifugal switch having a fixed contact75 and a pivoted contact arm 76 has been shown. Contact arm 76 is biasedto an open position by spring 77, when the associated machine 73 isidle. Contact arm 76 is pivoted to a closed position by means of asliding collar 79 slidably mounted on shaft 80 of centrifugal operator78. Pivoted links 81 connect collar 79 to flyweight arms 82. Flyweightarms 82 are pivotally connected to shaft 80 and when rotated thereby arecaused 6 by centrifugal action to pivot outwardly and transmit throughlinks 81 sliding action to the collar 79. Collar 79 engages aball-bearing on contact arm 76 and pivots the contact arm about pivotpoint 84 to close switch 74. Shaft of the centrifugal operator issuitably driven by an operating shaft 85 of machine 73.

The centrifugal switch and operator described above are generallydescribed in U.S. Patent No. 1,201,564, issued to P. U. Dancel October17, 1916. The particular centrifugal switch shown in FIGURE 5 is merelyillustrative of one of many types of switches which are actuated bymovement of a shaft and suitable for use with this invention.

The only necessary modification of the apparatus is the substitution forimpulse switch 10 of switch 74 which functions as above described.Contacts 76 of switches 74, associated with production machines 73, areconnected to a common ground. Contacts 75 are connected to respectivecontacts 29 of sampling switch 27 and to capacitors 32. The rotor ofsample switch 27 is driven at a constant speed, preferably at someconvenient hourly ratio such as revolutions per hour, if a samplingspeed of 100 revolutions per hour is selected.

The function of my production time counter will now be described. Assumethat all of the machines whose operations are sampled by sample switch27 are operating. The switches 74 will be closed. Each time sample rotor30 completes a revolution it has engaged each of the contacts 29 and acount has been recorded for each operating machine. Each count isregistered as one onehundredth of a machine hour. In one hourss time thecounting apparatus will have counted one machine hour of production foreach machine operating. If there are 60 machines associated with thesample switch and the machines have operated continuously for one hourof time, the total count will be 60.00 machine hours of production. Ifone machine is idle for a part of the hour, switch 74 will open and nocount will be recorded for the idle machine during each oneone-hundredth of an hour that the machine is idle. Assume that onemachine is idle for one-half hour, then the total production time countfor all of the machines will be 59.50 machine hours.

While in the foregoing there have been described and shown the preferredembodiment of the invention, various modifications may become apparentto those skilled in the art to which the invention relates. Accordingly,it is not desired to limit the invention to this disclosure and variousmodifications may be resorted to, such as may lie within the spirit andscope of the appended claims.

I claim:

1. In data sampling apparatus, the combination of a plurality ofindependent data impulse storing circuits, a source of erase potential,a rotary sample switch including a plurality of contacts in circuit withthe respective data impulse storing circuits, a sample rotor engageableindividually and successively with said contacts, and an erase rotorengageable individually and successively with said contacts, said eraserotor being positioned with respect to said sample rotor so that theerase rotor engages a particular one of said contacts immediately aftersaid sample rotor has left said particular contact, and so that saiderase rotor disengages said particular contact prior to the instant whensaid sample rotor engages the next succeeding contact, and switchingmeans for intermittently making connection between said erase potentialand the erase rotor each time an impulse is taken from said contacts bysaid sample rotor.

2. In data sampling apparatus, the combination of a plurality ofindependent data impulse storing circuits, a source of erase potential,a rotary sample switch including a plurality of primary contacts incircuit with the respective data impulse storing circuits, a pluralityof secondary contacts connected respectively to said primary contacts, asample rotor engageable individually and successively with said primarycontacts, and an erase rotor engageable individually and successivelywith said secondary contacts, said erase rotor being positioned withrespect to said sample rotor so thatthe erase rotor engages thesecondary contact which is connected to a particular one of said primarycontacts immediately after said sample rotor has left said particularprimary contact, and so that said erase rotor disengages the secondarycontact which is connected to the particular primary contact prior tothe instant when said sample rotor engages the next succeeding primarycontact, and switching means for intermittently making connectionbetween said erase potential and the erase rotor each time an impulse istaken from said contacts by said sample'rotor.

3. In counting apparatus, the combination of a plurality of independentdata impulse storing circuits, a source of erase potential, a rotarysample switch including a plurality of contact in circuit with therespective data impulse storing circuits, a sample rotor engageableindividually and successively with said contacts, an erase rotor whichapplies said erase potential to each data impulse storing circuitsuccessively immediately after each of said data impulse storingcircuits has been sampled by said sample rotor, switching means forintermittently making connection between said source of erase potentialand the erase rotor each time an impulse is taken from said contacts bysaid sample rotor, and a counter to receive data from said sample rotor.

4. In a counting apparatus, the combination of a plurality ofindependent data impulse storing circuits, a source of erase potential,a rotary sample switch including a plurality of contacts in circuit withthe respective data impulse storing circuits, a sample rotor engageableindividually and successively with said contacts and an erase rotorwhich applies erase potential to each data impulse storing circuitsuccessively immediately after each of said data impulse storingcircuits has been sampled by said sample rotor, switching means forintermittently making connection between said source of erase potentialand the erase rotor each time an impulse is taken from said contacts bysaid sample rotor, an impulse receiving tube connected to said samplerotor, a counter, and a counting relay in circuit with said counter andsaid tube whereby impulses delivered at random to reach of saidcontacts'are coordinated to sequentially actuate said counter throughsaid tube. V

5. Theapparatus as defined in claim 4 wherein said switching meansincludes an erase relay comprising a coil in circuit with said impulsereceiving tube and switch contacts in circuit with said erase potentialsource and said erase rotor.

6. The apparatus as defined in claim 4 wherein said switching meansincludes a switching electron tube.

7. The apparatus as defined in claim 5 including a damping capacitorconnected in'parallel with said erase relay coil.

8. In a counting apparatus, the combination of a plurality ofindependent data impulse storing circuits, a source of erase potential,a rotary sample switch including a plurality of contacts in circuit withthe respective data impulse storing circuits, a sample rotor engageableindividually and successively with said contacts and an erase rotorwhich applies erase potentialfto each data impulse storing circuitsuccessively immediately after each of said data impulse storingcircuits has been sampled by said sample rotor, an impulse receivingtube connected to said samplerotor, a counter, a countingfrelay incircuit with said counter and said tube whereby impulses delivered atrandom to each of said contacts are coordinated to sequentially actuatesaid counter through said tube, and a switching electron tube in circuitwith said erase potential source and said erase rotor and operable tointermittently make connection between said erase potential source andsaid erase rotor each time an impulse is taken from said contacts bysaid sample rotor, said switching tube including at least one controlgrid connected by circuit means to said sample rotor and said impulsereceiving tube, a cathode adjustably connected to said erase potentialsource, and a plate in circuit with said erase rotor.

9. The combination of a plurality of separate counting apparatusconnected to an impulse switch, each of said counting apparatusincluding a data storing network adapted to store impulses from saidimpulse switch, a rotary sample switch having a contact in circuit withsaid impulse switch and said data storing network, and a counter incircuit with said sample switch to receive impulses therefrom, said datastorage network comprising a capacitor connected on a first side incircuit with said impulses switch and ground, and on a second side incircuit with a source of current and ground, said circuit on said secondside including also a uni-directional valve which will permit saidcapacitor to charge when said impulse switch is closed, but will preventcurrent flow in a loop from one memory capacitor contained in onecounter to one memory capacitor contained in the other.

10. In counting apparatus for registering the total machine-hours ofproduction of a group of machines, a plurality of machines, operatingmeans for each machine, a plurality of independent switches in circuitwith a source of electric power, and each associated with a respectivemachine for detecting the operation of said machine, means associatedwith each machine for automatically closing its associated switch andkeeping said switch closed when the machine is operating, and meansconnected to said switches whereby each of said switches isautomatically opened when its respective associated machine is idle, arotary sample switch including a plurality of contacts in circuit withthe respective switches, and a rotor engageable individually andsuccessively with said contacts, an impulse receiving tube connected tosaid rotor, a counter and a relay in circuit with said'counter and saidtube whereby impulses are transmitted from said rotor to actuate saidcounter through said tube, and a constant speed drive means foractuating said rotor whereby said rotor samples the operating status ofeach of said machines at regular intervals.

References Cited in the file of this patent UNITED STATES PATENTS401,366 Osborn Apr. 16, 1889 1,789,811 Francis et al. Jan. 20,19311,845,534 .Waite Feb. 16, 1932 1,851,090 Fetter Mar. .29, 1932 2,074,037Watson Mar. 16, 1937 2,908,889 Piety Oct. 13, 1959

